Fire alarm



July 19, 1938. ,J. K.VGRONDAHIL' 2,124,488v

I FIRE ALARM Filqd Oct. 16,1937 2 Sheet-Sheet 2i Jens If. Grandakl I I '20 intense heat in the neighborhood, said device inare well known d form part of the Present- 20 40 fined to the disclosure, being susceptible of'such with the arm 29 on the bracket 20 and 1191858 Patented July 19,193a v t 2,124,488

UNITED STATES PATENT QFFICE' FIRE ALARM Jens K. Grondahl, Red Wing, Minn; Application ctober 16,'1937, Serial .No. 169,446

9 Claims. (01. 119-5) This invention relates toa fire alarm connected F gure 7 is a horizontal section through the with a telephone receiver. bracket for supp rt the alarm, a An obj t of th i v ti i th provision of" Figure 8 is a vertical sectionof a modified form a fire alarm which may be readily attached or of h a v r detached from a telephone receiver known as the Referring more p lyt the L 5 Fren ly' type and in which a spring-pressed. l0 designates a base member of a French teleplunger controlling a switch is held in an mopphone havi a p t I l rising from t as m m-. erative position by an arm which is retained in and P Ovided with Pairs of upstahdihg fingers an operative holding position by a fusible element, h fl l the Shank body p0rti0n 13 0f said arm also retaining a motor against operaa receiver, ra ly desig d y the e a 10 tion which when releasedwill actuate a mecha- 1 nism, for advising the telephone operator at the d P on is received between the Pairs switchboard that the building inwhich the tele- 0f fingers I2 a y ests upo t p' phone is located is on fire. sup o ead 5 carried by'the uppe end of 16 Another object of the invention is the pr'ovision a s -p essedplunger (not shown) which con- 5 f an attachment fo a French telephone for trols the closing of the switch when the receiver maintaining a switch conti.oiiing plunger in an! M is removed and the plunger rises in the post inoperative position until the device is released The body i provijied with mouth-Piece by the melting of a fusible element because of and an earpiece The Parts just described eluding a motorfor operating a phonograph loinvention i cated adjacent the mouth-piece of the receiver or bracket ghherany designated by for giving a signaladjacent the mouth-pi so meral 20, is provided with a U-shaped member that the telephone operator at the switch-board andvincludes, an arm ahridgihg Portion and 25 will be advised that a portion of the buildiflg is 11 depending m The members 24 and 25 25 on fire wherethe receiver is located so that such are disposed in Parallel relation and are Spaced operator can notify-the proper authorities of the sufficiently apart 9 that bracket may Y condition, pressed down over the portion Zl upon which rests A furth r object of the invention is the I vthe head Hi. The member 21 is formed integrally vision of a device for releasing the usual spring- Wlth the post The inner faces of the 30 pressed plunger of a'French telephone for closing 24 and 5 as Shown at 3; are p d W t the circuit, with means for giving audible signals rubber pads which frictiohahy grip e Side Walls for advising a telephone-operator.thatthe buildof the upper end of the Post H for aiding in a ing in which the telephone is located is on fire. maintainihg the bracket 20 ih Position This invention will be best understood from a h bracket is Provided with an Ofiset arm 29 consideration of the following detailed descrip- 'havmg the curved member. which engages tion in View of the accompanying drawings tomb around a casing 3 l, and is rigidly secured thereto ing a part of the specification; "nevertheless, it is for supporting said casing? to be understood that the invention is not con-' A lever 35 is normally located in flat tontact changes and modifications as define no material cured thereto a rock. Shaft which is rockably I 40 departure from the salient features of the invenmounted in the 51eeV37 Connected to the bracket tion as expressed in the appended claims. and forms a bearing for the ck Shaft 36.

i In the drawings: V A crank 38 is secured to the inner end of the,

Figure 1 is a from; i h m fire alarm shaft 36. A fingcr39 is secured to the outer free attached to a telephone receiver, I end of the crank and normally engages the head Figure 2 is a plan view. of the same, 15 0f the receiver for maintaining said head in Figure 3 i n end i I an inoperative position, as shown in Figs. 1 -and3. I Figure 41 a plan i of th signalling means The lever 35 is provided with a perforation 40 showing the cover partly broken away, while the arm 29 is provided with 'a perforation i i 5 is a fragmentaryjenlarged side view 4 and thes DEIfQIatiOHS e placed in alignment showing the stop inlocked position and retainwith each other and a fusible pin 42 is inserted in ing the mechanism against operation, these perforations for locking the lever 35 to the Figure 6 is a. vertical section of the alarm shown arm 29 so that the finger 39 will be maintained in in Figure 4,- l anfopera'tive position'forretaining the head I5 55 depressed. As shown in Fig. 1 the receiver- I4 is placed on the bridging member so that when the lever is released the head l5 may be raised in the usual manner because the re ceiver is anchored above said head.

The casing 3|, as-has been previously explained, is supported by the curved portion 30 of the arm 29 and the outer face 43 of said casing which is in the form of a removable cover, is held directly beneath the mouthpiece l6 of thereceiver. The casing is also provided with a removable bottom 44. I

A spring motor 45 is located within the casing ll and a winding knob 46 is secured to the shaft 41 which is connected with a spring motor in the usual manner. The knob-4.6 is provided with a slot 48 which is adapted to be received by some suitable tool for winding the motor. Connected with the motor is a train of gears, generally desi'gnated by the numeral 50, for operating a governor composed of the weightedmembers 5| and 52. Each weighted member is supported in the block 53 by meansof ,a rod-54. upon which is mounted a coil spring 55 having one end in enbe lowered. Naturally both nuts will-have to be adjusted the same distance.

The usual ratchet'wheel 56 and pivoted pawl 56a are employed for preventing unwinding of the spring when the motor is being wound. A spring 51 carried by the casing is adapted to maintain the pawl 56 in engagement with the teeth of the ratchet ii.

The shaft 41 adiacent the closure 43 is provided with a shoulder 60 on which rests a washer 8|. Upon this washer is mounted one end 62 of an arm 63 and a nut 64 is threaded 'onto the upper end of the shaft 41 for securing the member 62 rigidly to the shaft. The outer reduced end 65 of the shaft 4!v is mounted in 'a bearing 86 formed on the cover '43. I

The inner face of the cover 43 is provided with a plurality of lips 61 which are adapted to be engaged by the free end of the arm 63 when said arm is rotated so that these lips will be periodically engaged during rotation of the arm and give to the operator through the diaphragm 68 'where it is from. I Referring more particularly to Fig. 8 it will be seen that a modified form of the annunciator is-provided in which the shaft 41a is connected to a disc. Ill and provided with grooves of the -usual type of phonograph record. I

An arm II is secured tothe usual top 12 on the casing or box ila and the arm ll supports 'a needle 13 which has a stylus I4 engaging the record 10. The outer end of the needle or wire 13 is in contact with the diaphragm 68 of the telephone receiver.

As the disc 10 is revolved and the needle 13' movable means.

ceiver and must be removed before acall can be 'put through. In other words, the frame 20 may bedisengaged from the post I I while the plunger I5 is maintained by the finger of the operator inlowered position, since the frame is merely frictionally engaged on the post.

The alarm may be applied to the receiver when the house is being left vacant and as soon as the owner returns the alarm may be removed and the telephone receiver placed in its usual position. The casing 3| or 3la carries a shaft 15 operated by a knob or finger-piece 1.6. The inner end. of the shaft is provided with a pawl 11 which is adapted to engage. thegovernor including the arms 5i and 52, and thereby retain the motor 45 against operation. t

The knob 16 is. held in position by means of a pin 18 which engages the free end 19 of the lever 35. As long as the fusible element or pin 42 has locked the lever 35 to the arm 29 of the bracket 20, the free end 19 of said lever will engage the pin II and-prevent the governor from permitting the motor to be operated.

1. In a telephone receiver having a post and a spring-pressed circuit closing plunger in the post, a bracket removably mounted on the post and adapted to support the receiver in an inoperative position above the plunger, a lever pivotally mounted on the post, a finger on the lever engaging the plunger and retaining the same in an inoperative position, a fusible pin connecting the lever to the bracket against movement, an alarmcarrieiby the bracket and disposed adjacent the mouthpiece of'the receiver, means for operating the alarm and means engagedby the lever for retaining the operating means for' the alarm against movement. until the fusible pin releases said lever. v

2. In a telephone receiver having a post and a spring-pressed circuit closing plunger in the.

erativeposition above the plunger, a lever pivoted on the bracket and having means engageable with the plunger for, normally. depressingsaid plunger, a fusible pin for retaining said lever against movement to hold the plungerengaging means on the lever in an operative position, an

alarm associated with the mouth-piece. of the.

receiver, means for operating the alarm, and means for retaining the ope'ratingmeans against action, said lever engaging the retaining means until the fusible pin releases the lever.

3., In a telephone receiver having a post and a spring-pressed circuit-closing plunger in the post, .a bracket removably mounted on the post and adapted to .support the receiver in'an inoperative position above the plunger, movable means on the bracket for retaining the plunger depressed, a fusible element for retaining the movable means in operative depressing relation with theplunger, an alarm on the bracket and disposed adjacent the mouthpiece of the receiver,

operating means for' the alarm, cooperating means on the operating means and-the movable means for retaining said operating means against action until the fusible element releases the 4. In a telephone receiver havinga post and a tor for actuating the alarm, means for retaining.

the motor against operation, said'movable means engaging the retaining means and adapted to release said retaining means when the fusible element has been melted. I

5. In a telephone receiver having a post and a spring-operated circuit closer, means for supporting the receiver in an inoperative position above the closer, a lever removably mounted on the post and having means for. retaining the closer open, an alarm adjacent the mouth-piece of the receiver, means for actuating the alarm, said lever retaining the actuating means against operation, a iusible element for retaining the lever against actuation by the spring-operated closer,

6. In a telephone receiver having a post and, a spring-operated circuit closer, a bracket having spring arms for removably' connecting the bracket to the post, said bracket having asupport for the receiver for maintaining said receiver out of contact with the closer, movable means on the bracket for retaining the closer in open position,

r a fusible element for maintainingthe movable means in anoperative position on the bracket an audible'signal supported by the bracket adja- Y cent the mouthpiece of the receiver, means for operating the signal and cooperating means on the operating means and the movable means (or holding the operating means against'actuation'. 7. In atelephone receiver having a poet and a spring-operated circuit closer. a detachable means mounted on the, post for supporting the receiver out oi contact with the circuit closer, movable means on the detachable means for retaining the closer-open, a fusible element for holding the movable means against operation, an

alarm adjacent the mouthpiece or the receiver and having a rotary element, means for rotating said element, the movable means. retaining the rotating means against operation," and means in the alarm and 'perlodicallyengaged by the rotary element for producing a signal which will indicate to the telephone operator that a building is on fire. a

8. In a telephone receiver having a post and Y a spring-operated circuit closer, a detachable bracket mounted on the postand having a support for maintaining the receiver out oi! contact with the closer, a movable means on the bracket for retaining the closer open, a fusible element for holding the movable means ag'a'inst operation,

an alarm adjacent the mouth-piece of the receiver and having a rotary element, means for rotating said element, the movable means retaining the rotating means against operation, and means in the alarm and periodically engagedby the rotary element (or producing a signal which will indicate' to the telephone operatort'hat a building is on fire. 9. In a telephone receiver having aspring-op- Y erated circuit closer normally held inoperative by the weight of the receiver, means for supporting said receiver out of operative relation with the circuit closer, an alarm adapted to influence the mouth-piece of the receiver, means forcperating the alarm and meansretaining thela'st mentioned means and the closer in an inoperative position and including a iusible means.

JENB K. GRONDAEL; 

